This invention relates to a structure of connecting battery terminals to bus bars, and more particularly to such a structure in which short-circuiting will not occur between a pair of bus bars respectively connecting terminals of a high-voltage battery, mounted on an automobile, to a relay block.
Generally, a battery, having a rated voltage of 12V (maximum voltage of 14V) has heretofore been mounted on passenger cars, and the maximum voltage of 14V is supplied from the battery to bus bars or the like within an electric connection box, and the electric power is distributed by internal circuits in the electric connection box, and through wires, connected to the internal circuits, electrical equipments, mounted on the automobile, are controlled, and also signals are transmitted and received.
In recent years, the number of electrical equipments, mounted on an automobile, is increasing, and besides there is a tendency to increase the amount of supply of electric current to each electrical equipment, and therefore there is proposed a construction using a high-voltage battery for supplying a higher voltage (e.g. 42V) than that of the conventional batteries.
As shown in FIG. 6A, high voltage is applied to internal circuits of a relay block 1 connected via bus bars 2 and 3 to a plus (+) terminal 101 and a minus (−) terminal 102 of the high-voltage battery 100, and the internal circuits form branch circuits so as to control the supply of the electric power to various electrical equipments, and circuit protection function parts, such as a fusible link 1a and fuses 1b, are provided to prevent excess current from flowing to the electrical equipments.
However, the bus bars 2 and 3, connecting the high-voltage battery 100 to the relay block 1, are exposed to the exterior, and therefore when a screwdriver D or the like is inadvertently placed on the bus bars 2 and 3 during the working in such a manner that a metal portion Da of the screwdriver D connects the bus bars 2 and 3 together in a bridging manner as shown in FIG. 6B, short-circuiting occurs, and this is particularly dangerous since the voltage of the battery 100 is high.